MAKE Podcast

ChangeMAKErs - Dr Curt McCartney

September 01, 2023 Manitoba Agriculture & Food Knowledge Exchange Season 2 Episode 2
MAKE Podcast
ChangeMAKErs - Dr Curt McCartney
Show Notes Transcript

Welcome to ChangeMAKErs, a new MAKEManitoba podcast series highlighting research and innovation powered by members of the Faculty of Agricultural and Food Sciences.

In this episode, host and FAFS research facilitator Dr. Chantal Bassett chats with Dr. Curt McCartney, Associate Professor in the Department of Plant Science, to chat about his research in wheat breeding, genetics and genomics, especially in the areas of winter survival, yield, and disease resistance.

Intro:

The way we grow and produce food is ever-changing, shaped by consumers and the climate in which we live and farm. Research at all points of our food system is essential for continuously improving food's journey from farm to table . The Manitoba Agriculture and Food Knowledge Exchange explores timely research, innovations and applications that make our food system better than ever. Join us for today's podcast.

Chantal Bassett:

Hello and welcome. This is ChangeMAKErs, a Manitoba Agriculture and Food Knowledge Exchange, otherwise known as MAKE podcast series with me Chantal Bassett. In each episode, we'll chat with an academic member of the faculty of Agricultural and Food Sciences at the University of Manitoba to find out about the research and innovation they're working on and how this is shaping agriculture and food production in Manitoba and around the world. Now, as the research facilitator for the faculty, I get to work with all our incredible innovators, and I think it's high time for others to get to know their research as well as get to know the person behind these discoveries. Today I'm joined by Dr. Curt McCartney, our very own wheat breeding and genomics expert within the Department of Plant Science. Thanks for joining me, Curt.

Curt McCartney:

Thank you very much, Chantal.

Chantal Bassett:

So Curt, before we get into the details about what you study, can you please share how you got to where you are today?

Curt McCartney:

Okay. I grew up on a grain farm , near Portage La Prairie , Manitoba. Growing up I was reading a lot of the farm magazines that my dad had. And , I got interested in production issues that were discussed and talked about in these articles about Sclerotinia, having Blacklegs in canola, there's emerging Fusarium Head Blight is a problem and in wheat. And so I got interested from there. And then in high school I really enjoyed biology courses and in particular, genetics. I was always interested in that and that particular topic. And then during my undergraduate degree at the University of Manitoba, I took the genetics program and this led me to take a course in plant breeding and I was hooked right away. It kind of merged everything I was interested in , from farming and also genetics and kind of put it all together into something that would be quite unique and quite interesting in terms of a career. That's how I got interested in the field and why I ultimately ended up doing it.

Chantal Bassett:

So what path did you take that led you to becoming an academic within our faculty?

Curt McCartney:

Yeah. So after I completed my undergraduate degree, I spoke with the former wheat breeder here at the University of Manitoba, Dr. Anita Brûlé-Babel. I ended up doing graduate studies with her studying genetics and resistance to one of the leaf spotting diseases of spring wheat. So I started off in a Master's program, which ultimately ended up being a PhD and then I went and did a postdoctoral position with Agriculture and AgriFood Canada here in Winnipeg. And then from there I joined the University of Saskatchewan Crop Development Center as a cereal and flax pathologist with them. And then I was there for 5 years and then ultimately came back to the Ag Canada, Winnipeg program in 2010. Worked there for 10 years as a geneticist working on wheat and oates. And then ultimately I rejoined the University of Manitoba as a wheat breeder in 2020.

Chantal Bassett:

And we're great that you have brought all this wealth of experience throughout your career, and so you're relatively new to the University of Manitoba, but you are bringing such a wealth of knowledge.

Curt McCartney:

Yeah. Thank you.

Chantal Bassett:

So Curt, what's the focus of your research? What challenges are you trying to solve?

Curt McCartney:

Well, there's different sort of areas of the work. One would be in the area of genetics, to get a better understanding of the genetics of wheat. And the other one is actually breeding the crop. So in the area of genetics, I'm trying to better understand the inheritance of traits that matter to farmers, also to the wheat industry overall and ultimately to consumers. So this is gonna range from disease and insect resistance, which will prevent damage to farmers' crops and ultimately reduce the need or ultimate use of pesticides in crops. So in particular, insecticides and fungicides can be reduced through the use of genetic resistance in varieties that the farmers are growing. And I guess one of the other things that we're doing with the genetics is answering some of the fundamental questions, how many genes are involved in controlling a particular trait? And can we identify DNA markers that we can use to track the inheritance of these genes in breeding programs? So then the area of wheat breeding I'm working on winter wheat with the goal of developing varieties for Western Canada. In the breeding program we're implementing what we're learning from the genetic research. In the case of winter wheat, the main thing we're trying to improve upon at this point in time, would be winter survival. It still remains an important limiting factor for production of winter wheat in the prairies. Either develop more consistent varieties that are at the best of the range of winter survival, but also shoot past the current sort of upper limit of winter survival that we currently have. In addition to that, there are all the other typical traits that wheat breeders are concerned with: grain yield, disease resistance, and grain quality. So that would be typical of the other breeding programs that working in spring wheat. And then I guess the final thing my lab does is we also test wheat and triticale breeding lines from breeders across the prairies. These would be both spring sewn and and false sewn types of these crops. And we're testing them for resistant to Fusarium Head Blight, also commonly known as FHB, FHB is the most destructive disease of wheat in Canada in many other parts of the world. So there's a lot of need for developing resistant varieties to this particular disease. So it's affecting the farmers, but it's also affecting the millers and the people breaking baking bread as well. So it has a big impact on everybody, and there are limits to the amount of the toxin that the fungus produces in the grain. So that will limit the harvested grain from a field might not sell for the top price if it has a lot of that particular toxin in it. So we ultimately collect this information on the new breeding lines that are being developed, and we send that back to the breeders that are operating in different prairie provinces, and then they use that information to throw away the really susceptible stuff. And as a result of this work, the level of resistance in the varieties is improving over time.

Chantal Bassett:

Okay. So in terms of end goal, I've heard that, you know, reducing pesticides, fungicides and also in terms of quality, in terms of the flour that we could derive for different products based on different wheat varieties. Curt, is there also any impact of climate change? Is that a reason why we're exploring different types of wheats and resistance beyond just disease and pests?

Curt McCartney:

Well, climate change is gonna have a really important impact on crop production in the prairies and really anywhere in the world, farmers are very much at the mercy of the weather. So what I'm thinking with climate change, we're likely to see basically a migration of the crops in the US up to Canada. And in terms of the length of growing season's gonna get longer, we're gonna see some of the crops that they're growing down there, maybe a little bit more commonly up here. We're already seeing it already with a lot more soybean being produced and things like that. So in the area, so with my work on winter wheat I'm expecting though winters, well, I'm hoping, hoping we're expecting that the winter get a little bit milder and we're gonna see increased winter survival and the winter hardiness of the crop is likely to become less critical over time. So I think there's gonna be opportunities for winter wheat in the future. So I think that's one thing to consider with climate change. Breeding programs are, are long-term research efforts and you can't just start and stop them quickly or on a dime, essentially. There is a real need for the breeding of winter wheat that is locally adapted to the weather conditions here. But I'm expecting these weather conditions to change over time. I guess the final thing I was thinking of just breeding in general as a broader topic, it's really important to have active plant breeding programs in all crops to allow our crops that we're growing to adapt to the new environment because active breeding programs are constantly selecting for the new environment that they're facing. So the crop that they're developing is changing every year. I think that's another important thing to consider is it's really critical to have these breeding programs operating or you're effectively, if you don't have them, you're locked in time with a certain set of genetics which might not fit the future.

Chantal Bassett:

So Curt, what impact do you hope your research will have?

Curt McCartney:

So I guess I'd like to see winter wheat production increase in the prairies. I think we're gonna need improved winter survival to accomplish that goal. And I think the other piece of the puzzle is increasing grain yield relative to spring wheat to make the crop a little bit more financially attractive to entice farmers into growing it more commonly or more often. I'd also like to see with the research we're doing on the Fusarium Head Blight resistance to result in and continue slow march towards a really strongly resistant set of germ plasm such that we don't have much problems with Fusarium Head Blight anymore in our fields. It's really critically important disease to get under control. And the genetics of the resistance is really complicated compared to the other diseases. The progress that we've been making has taken more time than you'd like to see, but it's really important that we get that to happen. So I'm expecting we are gonna get there. And these nurseries that we're growing for testing these new breeding lines is critically important for achieving that goal because there's no other way to assess whether it's resistant or not other than these field trials. I think the final area that I'm hoping to make impact in, is in the training of graduate students in the area of plant genetics and crop breeding. We need to be training new people to take over these positions as people are retiring and to further move ahead how we're actually doing these types of research projects and, and getting new ideas into our work is really important. And then I guess finally would be in the area of teaching undergraduate students as well in the area of genetics teaching. It's quite a bit of fun.

Chantal Bassett:

So I assume that many, you know, farm kids across the prairies are relying on going to programs such as the UofM's to learn some of the basics so that they can recognize emerging diseases, recognize things before they get outta hand on a farm. Is that part of your teaching mission?

Curt McCartney:

Yeah, I think it's very hard to predict what's gonna be the new thing or the new problem. I think we do our best we can with that. But it's often we don't really know what's gonna happen ultimately with a lot of these diseases. So yeah, I think we do want to be training people in the fundamentals of say, plant pathology or entomology and a whole wide variety of different disciplines that matter. So they have the tools that they can adapt to whatever the future throws at them. I don't think anyone would've guessed that Fusarium Head Blight, I guess maybe 20 or 30 years ago, now would've been a problem, say in the 1970s. No one was thinking, oh , if Fusarium Head Blight was on nobody's radar that it gonna be a problem for wheat. We are concerned with some evolving rust races that have developed in other parts of the world, and we do some preemptive work with sending breeding lines to areas where these new races are to see if we can identify resistance to them in our own breeding material. So that's some something we can do. But then there's other diseases like Wheat Blast, which is found now in South America. I think it's now also into the southern United States. It's caused by a plant pathogen that we've never really experienced here in Canada. So it's something to keep on the radar screen, but it's hard to justify spending a lot of time and effort on something when we have a whole suite of problems we're currently facing. And there's the imminent threat right now is the current one. So that's, I would say that's kind of, we have to triage these things a little bit and figure out what and where our priorities have to be. But yeah.

Chantal Bassett:

How do you decide which trial to run in an upcoming year and how far in advance do you plan the research studies that you undertake?

Curt McCartney:

Well, the studies themselves, you just think about, I guess in terms of as a breeder, what is currently my limitation or something that I would like to be able to do better. And that can lead to a whole suite of genetic studies you could conduct to learn about the trait better and develop tools that would help you select for a particular improvement in the trait. So that's be one thing, and those things take time. Often a genetic study might take 4 or 5 years to complete from the stage of conception to you've completed the project. But at the same time, like our breeding program, we're often planning the trials in the period of about 2 weeks where you harvest one crop early August, and then we're seeding in September, so we don't have a lot of time to plan the next set of material we're putting out into the field. So it's a bit of a rush at that time of the year. It just depends exactly at what level you're considering this at. We have a general plan for the breeding program, and that's a long-term plan, so that part doesn't change. And the actual material that we're testing every year is just kind of, it follows a typical path. I would say. The genetic research is something that is a little bit more variable, have to figure out what the priority we think is so something that's holding us back currently that we'd want to have better knowledge of so we can do it better in the future.

Chantal Bassett:

Yeah. So in terms of the studies and the who you're training, like you talked about, you're training the next generation of plant breeders, but what other careers might be relevant to that? And maybe help me understand how a plant breeder, is it mostly time in a laboratory or is it mostly time in the field?

Curt McCartney:

Well, It's a bit of both. We do a lot of work in greenhouses in the summertime or in the field primarily. And then the wintertime we have a lot of work where we're working in the lab either processing seed and getting it ready for seeding or in the case of our Fusarium testing, we're basically getting our seed ready and prepared for sending off to another lab that will test the Fusarium damage kernels and the levels of toxin in the grain. So that would be one thing. Then I guess we also, in the winter time , we spend more time working on DNA markers extracting DNA testing DNA markers so that we can have a better idea of what our breeding lines are from that perspective. And of course, in the winter time , the wheat is just sitting in a field as a tiny little cold shivering seedling, so that it's not doing a whole lot of that point in time. But , we are still busy year round .

Chantal Bassett:

And does a wheat breeder collaborate with other types of researchers?

Curt McCartney:

Oh, yeah. There's a lot of collaboration, even like in amongst the wheat breeders themselves, there's a whole lot of exchanging of different tests across the prairies that wheat breeders are doing. We work with a whole bunch of plant pathologists who specialize in different diseases of the crop . Different diseases are more prevalent in different parts of prairie, so the best person to study, say Stripe Rest, is located in Lethbridge, Alberta because that's where that disease is common. And in Manitoba we have more problems with Leaf and Stem Rust and Fusarium Head Blight. So this is where those diseases are tested. So we have a lot of collaboration on it with plant pathologists . We have collaborations with entomology , entomologists working on Wheat Midge . There's also some people working on Weed Stem Soft Fly. So that'd be another areas of collaboration. And then finally there's a whole bunch of people working in grain quality. So we work with them in terms of trying to ensure the new bring lines that we're developing have meet the expectations our customers have, but also we can also work together on genetic studies to have a better understanding of what makes good grain quality.

Chantal Bassett:

So Curt, what's the most interesting or surprising thing that you've discovered so far?

Curt McCartney:

I think something that's come up repeatedly over the course of the research I've been doing is how interrelated different traits are. One of the big things that occurred, I would say is definitely not my opinion, but it's the Green Revolution. The introduction of semi-dwarfing genes into wheat for reducing plant height was really important globally and also in Western Canada for reducing the height of the crop and reducing crop lodging. Crop lodging is a really important problem. So that's when the crop is basically fallen over in the field as the grain is filling in the heads. And that causes all sorts of problems for harvest. It also causes problems with sprouting of the grain as it's ripened in the field. The introducing of these dwarfing genes, semi-dwarfing genes, has prevented a lot of the lodging problems that we used to experience. It's also meant that farmers can now straight cut , combine their fields and they don't have to swath. And I don't think really any swathing of weeds has done really anymore. So there's been a whole lot of incentive to do this, but there has been maybe some problems with the introduction of these semi-dwarfing genes. It's come up repeatedly in the genetic studies that've conducted. So one of the thing that's really widely known is that the shorter plant height is also associated with shorter uptals. So as the crop or the seeds are germinating, the uptal is what gets the chute tissue above the soil surface. So this means that varieties that have these semi-dwarfing genes cannot be sewn as deep in the soil. So that can cause emergence problems if a farmer is trying to seed deeper to get access to moisture, to get the seed to germinate. So that's one issue. The work, I've done in genetic research on FHB resistance, and this is not just me, but many people around the world have found that semi-dwarfing genes are associated with susceptibility Fusarium Head Blight. And that includes, there's 3 major genes that have been used. They're called RHD 1, 2, and 8. And these genes, all of them have been associated with increased susceptibility to Fusarium Head Blight, but there are additional semi-dwarfing genes that have identified that haven't been used commercially in wheat breeding. There's a lot of interest around the world, and I'm quite interested in this as well, looking at these new dwarfing genes to see if we can swap out the old ones and put in these new ones and to see if we can overcome some of these problems. There are dwarfing genes that we do know have no effect on colloidal length, so they clearly are different than the current ones. If we can find ones that also don't have any effect on or association with susceptibility Head Blight, that could solve some of the bigger problems we're experiencing with Fusarium Head Blight, because I think if you took out some of these dwarfing genes out of the current varieties and had a taller version of those varieties, they'd be a lot more resistant to Fusarium Head Blight. So that's something I'm quite interested in. And so this kind of theme of these interrelationships between these traits has come up all the time. So I wasn't necessarily expecting this when I first started off in my career as a scientist. And it's been quite interesting to learn about how all these things fit together and how these things , these interrelationships are the reality that breeders have to work with. And it's interesting work, and that would be the thing that's been the most surprising to me.

Chantal Bassett:

That's awesome. So, thanks for all the research that you are doing in terms of, you know, I know that it is impacting, you know, active problems that our, you know, farmers are facing and then all the way to different customers and the end products that we're having. So I'm really grateful that you know that you are taking the time to lead these research initiatives that are helping with winter wheat across Canada. So before we finish off, Curt, can you tell us something about yourself that is unrelated to your research?

Curt McCartney:

Well, maybe from the result of the pandemic, I think all of us has spent a whole lot of time indoors and I'm pretty guilty of being , becoming a TV addict, so I'm, I'm watching way too much TV and still trying to get outside more. But we've accumulated as a family, a whole bunch of streaming subscriptions and, and I really like murder mystery shows and I can recommend Only Murders in the Building. Yes, that's an awesome one . So people may wanna check that one out.

Chantal Bassett:

Awesome. Currently watching it as well at home, this has been Dr. Chantal Bassett, joined by Dr. Curt McCartney, associate professor in the Department of Plant Science at the University of Manitoba. And that's it for today's episode of Change Makers , the Faculty of Agricultural and Food Sciences Research and Innovation podcast. Join me in future episodes to hear about other fascinating research being led by agricultural and AgriFood innovators at the University of Manitoba.